Synthesis of Copper and Copper-Ruthenium Nanoparticles in Ionic Liquids for the Metallization of Advanced Interconnect Structures

Abstract

Bimetallic nanoparticles can be used in a variety of applications such as catalysis, in advanced magnetic or optical devices or as starting materials to form continuous metallic layers. In this study, we report the synthesis of bimetallic ruthenium-copper (Ru-Cu) nanoparticles in ionic liquids. For this purpose, solutions of ionic liquids containing a mixture of precursors of Ru and Cu were decomposed under dihydrogen. Small, crystalline and well dispersed Ru-CuNPs (2.5 ± 0.6 nm) were obtained, which are significantly smaller than the pure Ru or pure CuNPs formed under the same conditions. Our analyses suggest that these NPs have a Ru core -Cu shell structure. This structure is expected from thermodynamical and kinetics data. Moreover, this could explain the dramatic size reduction observed when mixing the two metals.

Small nickel nanoparticle arrays from long chain imidazolium ionic liquids

“…† To explain the poorer size control we may look at kinetics of NP formation. Similar to Cu-NP formation from decomposition of CuMes reported by Arquillière et al, 38 a higher energy barrier is involved in the decomposition of Ni(COD) 2 . Thus, the formation of nuclides is slow.…”

Ligand-free copper(i) oxide nanoparticle-catalysed amination of aryl halides in ionic liquids

“…3,4 In the last decade, scientific research has focussed on the development of inexpensive and less toxic metals such as iron [5][6][7][8] and copper. [9][10][11] One promising catalyst turns out to be copper(I) oxide which showed remarkable activity in homogeneous as well as heterogeneous C-N bond formation reactions. [12][13][14] Homogeneously driven copper(I) catalysed C-N bond formation sometimes requires only homeopathic catalyst loadings, but the use of ligands, base or other additives as well as inert conditions are usually necessary.…”

Recyclable nanoscale copper(i) catalysts in ionic liquid media for selective decarboxylative C–C bond cleavage

“…38,40,43 There are some reports about application of copper and copper oxide nanoparticles in ionic liquids, however most of them are related to electrochemistry and microelectronics and only very few report about application as catalysts in the wide field of organic synthesis. 37,38,40,[44][45][46][47][48][49][50][51][52][53][54] The first report about colloidal copper catalysts for the coupling of aryl halides and activated olefins was reported by Heck and Nolley in 1972. 54 More recently, it has been shown that nanoscale copper catalysts are released from copper bronze in ionic liquid media and these particles were active in the Heck reaction.…”